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It is known that the intermetallic compounds RT2, RT3, %T7, F$Tlg, and RT5 can form in the series of the rare-earth(R) and 3d(T) metal alloys. From the structural point of view the lattices of the compounds RT3, %T,, and F$TI9 a r e combinations of elementary parts F$T4 (2RT2) and RT5 packed along the common axis at symmetry of third order: 3RT3 = F$T4 + RT5, 2 5 T 7 = F$T4+ + 2RT5, %Tlg =R2T4 + 3RT5. If the packing of parts F$T corresponds t o the hexagonal Laves phase of the MgZ% type, the structure of the compounds belongs t o the space group R3/mmc (the hexagonal modification of the compounds RT3, %T,, %Tlg). When the parts %T4 a r e packed as in the cubic Laves phase of the M g C 3 type, the structure belongs to the space group m-m (the rhombohedral modification). Up t o now each of these compounds was prepared either as only one modification o r as an indivisible mixture of two phases. There was no compound obtained separately in both modifications.The Tb2C07 single crystals of the rhombohedra1 ( a ) modification were investigated in /l/, where an unusual type of three-axes magnetic anisotrow was observed. In our note single crystals of this compound in the hexagonal ( 8 ) modificiation a r e obtained and a comparison of magnetic properties is made for the same compound but with different symmetry of crystals. 4A determination of the modifications was carried out from the symmetry at the Laue patterns obtained at diffraction from the (110) and (100) crystallographic planes (along the axes a and b, respectively). In @-crystals a and b axes a r e the 1) Ke Karlovu 5,